Inlet port plug

ABSTRACT

The present invention is an apparatus, or plug, for closing an inlet port. The inlet port is formed in a sheet of a typically flexible material. The inlet port is designed to mate with an air hose nozzle. The plug blocks the inlet port when no air hose nozzle is engaged. The plug has a generally planar shape with coplanar extensions extending radially from the plug body. The plug is engaged by causing at least two of the extensions to be received in the inlet port. When the extensions are received, the plug is retained gains the inlet port.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a continuation of U.S. patent application Ser. No.09/368,206, U.S. Pat. No. 6,214,755 filed Aug. 4, 1999, titled “INLETPORT PLUG FOR INFLATABLE THERMAL BLANKETS”, which is a continuation ofU.S. patent application Ser. No. 08/624,101, filed Mar. 29, 1996 nowU.S. Pat. No. 5,997,572, issued Dec. 7, 1999, titled “INLET PORT PLUGFOR INFLATABLE THERMAL BLANKETS” and is also related to U.S. patentapplication Ser. No. 09/496,599, U.S. Pat. No. 6,228,107 filed Feb. 2,2000, titled “INLET PORT PLUG FOR INFLATABLE THERMAL BLANKETS”.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to devices for warming a patient during amedical procedure, and more particularly, to an apparatus forrestricting air flow through an inlet port in an inflatable thermablanket used to warm a patient during a medical procedure.

2. Description of the Related Art

Hypothermia, a condition in which a person's body temperature dropsbelow normal, presents serious potential consequences to a patient.Studies have shown that hypothermia occurs in nearly 75 percent of allpatients who undergo surgical procedures. Based on recent numbers, thismeans that 14 million patients a year in the United States alone sufferfrom hypothermia during surgical procedures. Hypothermia during surgerymay be caused by anesthesia, air conditioning within the operating room,infusion of cold blood, IV solutions, and/or irrigation fluids, inaddition to other factors.

One well known method for reducing hypothermia during surgicalprocedures is to place an inflatable thermal blanket over a patientduring a surgical procedure. The thermal blanket is inflated with awarmed airstream, exhausting warmed inflating air onto the patient. Aninflatable thermal blanket was first disclosed in U.S. Pat No. 4,572,188assigned to Augustine Medical, Inc., the assignee of the presentapplication. U.S. Pat. No. 5,405,371, also assigned to AugustineMedical, Inc., is directed to an inflatable thermal blanket that extendstransversely across the arms and chest of a patient's body, and is foruse during surgery at or below the patient's chest. These patentsdisclosed an airstream inlet: In later products, the airstream inletport comprises a cardboard structure adhesively attached to the surfaceof the thermal blanket A hole provided through the inlet port is sizedto accept the end or nozzle of an inflation hose. In some thermalblankets, a plurality of inlet ports are provided to allow an inflationhose to be attached at any one of a plurality of locations on theblanket. When an operator inserts the inflation hose into an inlet port,the port is closed about the hose. The surface material of the thermalblanket which coincides with the inlet port is either removed orperforated in order to allow a warmed airstream to pass from the hosethrough the port to the interior of the thermal blanket. The warmedairstream enters the thermal blanket and is forced out a plurality ofsmall exhaust holes in the lower surface of the thermal blanket.Typically, the user perforates or removes that portion of the thermalblanket which covers an inlet port only when that port is to be used.Accordingly, each of the unused inletports remains sealed until afterthe first use.

One problem with this design is that if the operator decides in themiddle of the procedure to move the inflation hose from one inlet portto another, the first port must be resealed or otherwise closed in orderto prevent air from exiting through that port instead of through theholes on the lower surface of the blanket, as intended. A number ofmeans have been used to reseal or close an inlet port after removal ofan inflation hose. However, none of these means are completelysatisfactory. For example, tape has been used to seal an open port, butis generally a nuisance to apply. The prior art suggests many othermeans and modes for sealing or closing an open port including: adhesivestrips, double sided tape, snaps, zippers, folding flaps, Ziplock®-typeseal, hook and loop fastener strips, folding wire, or plastic bars. Eachof these methods has a number of drawbacks. The method is eitherrelatively costly, or it is inconvenient, requiring a great deal ofattention or time of an operator, possibly during critical moments. Suchmethods and means require accommodation in manufacture of a thermalblanket, increasing production costs and decreasing manufacturability.

Accordingly, it would be desirable to provide a method and apparatus forclosing inlet ports in an inflatable thermal blanket such that the portmay be opened and closed conveniently and repeatedly.

SUMMARY OF THE INVENTION

The present invention is an apparatus for conveniently closing openinlet ports with an inlet plug. The inlet port is in a generally planarsheet of material that is flexible and/resilient. The inlet port has ashape that permits an air hose nozzle to be engaged with the port. Whennot engaged by an air hose nozzle, the inlet port can be sealed with aplug. The plug prevents air from escaping through the inlet port. Theplug has a generally planar body with coplanar extensions extendingradially from the body. At least two of these extensions are receivedinto the inlet port to retain the plug against the inlet port.Typically, at least the extensions are made from a resilient material sothat the extensions can be easily flexed, and be returned to a coplanaralignment with the plug when released. The plug body can be of the samematerial as the extensions, or have other flexibility characteristicsconsistent with materials such as wood or plastic.

The extensions can be circular, triangular, or rectangular in shape toimprove the release, retention, and ease of use of the plug. In someaspects, the plug includes pairs of opposing extensions. The extensioncan also be formed with non-planar distal ends to be received in theinlet port. In other aspects of the invention, the distal ends of theextensions are notched. Additional details of the inlet port closingapparatus are provided below.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is an illustration of the preferred embodiment of the presentinvention.

FIG. 2 is an illustration of the preferred embodiment of the presentinvention immediately before insertion into an inlet port.

FIG. 3 is an illusion of the preferred embodiment of the presentinvention after insertion into an inlet port.

FIG. 4 is an illustration of an alternative embodiment of the presentinvention.

FIG. 5 is an illustration of the alternative embodiment of FIG. 4immediately before insertion into an inlet port.

FIG. 6 is an illustration of the alternative embodiment of FIG. 4 afterinsertion into an inlet port.

FIG. 7a is an illusion of an embodiment of the invention having a distalend of an appendage tilted up ward.

FIG. 7b is a side view of the embodiment of FIG. 7a.

FIGS. 8a-8 e illustrates a number of alterative embodiments of theinvention having varied appendages.

FIG. 9a is an illustration of an embodiment of the invention havingprotuberances.

FIG. 9b is a side view of an embodiment of the invention havingretractable protuberances.

FIG. 10 is a side view of the embodiment of FIG. 9a.

FlG. 11 is an illusion of the embodiment of FIG. 9a suspended over aport.

FIG. 12 is an illustration of the embodiment of FIG. 9a inserted in theport

FIG. 13 is an illustration of an embodiment having threads.

FIG. 14 is an illustration of the embodiment of FIG. 13 after insertionin the port.

FIG. 15 illustrates the present invention in use with a conventionalupper body inflatable thermal blanket.

FIG. 16 shows the present invention in use with a lower body inflatablethermal blanket.

Like reference numbers and designations in the various drawings refer tolike elements.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

Throughout this description, the preferred embodiment and examples shownshould be considered as exemplars, rather than as limitations on thepresent invention.

Overview

The present invention is a plug for removably closing an inlet port ofan inflatable thermal blanket. One preferred embodiment of the presentinvention is shown in FIGS. 1-3. As shown FIG. 1, the plug has a centralbody 102 that is essential circular and has a diameter equal to that ofan inlet port with which the invention is to be used. Extendingpreferably radially outward from the central body 102 are a plurality ofextensions 103. In this embodiment of the present invention, an evennumber of opposing extensions are provided, as shown in FIGS. 1-8. Theseextensions 103 may be substantially curved, or rounded, like the leavesof a 4-leaf clover. Alternatively, the extensions may be generallypointed, as shown in FIGS. 4-6. Preferably four extensions 103 areprovided However, fewer than four extensions may be provided or, asshown in FIG. 4, more than four extensions 403 may be provided. Thenumber of extensions is generally unrelated to the shape of each of theextensions. In accordance with the preferred invention, the plug is madeof a generally flexible, resilient sheet of material, such as plastic ora wood pulp product, such as paper or cardboard. Preferably, thematerial is rigid enough to allow bending along a central axis throughthe center of the plug in predominantly one direction at a time. Thematerial is preferably die-cut into the desired shape. Alternatively,the material may be stamped, extruded, molded or otherwise formed intothe desired shape.

In accordance with one method of the present invention, the plug is bentsuch that outer edges of opposing extensions may be inserted into aninlet port 201 (see FIG. 2). The inlet port is typically a circular holethrough a rectangular sheet 203 of cardboard. The sheet has a first (or,outer) surface 204, and a second (or, inner) surface indicated byreference numeral 206. Slits 205 about the perimeter of the port 201allow the port to accommodate an end or nozzle of an inflation hose (notshown) which is slightly larger in outside diameter than the innerdiameter of the port As shown in FIGS. 3 and 6, when the plug 100 isreleased, the plug flattens across and substantially, if not entirelycloses the port 201. The plug is retained in the port by the extensionsthat engage the second (or, inner) surface of the sheet 203. Preferablyan equal number of extensions 103, 403 are placed inside the port 201 asremain outside the port although this is not vital to the practice ofthe invention.

In an alternative embodiment of the present invention shown in FIGS. 7aand 7 b, the distal end of one or more of the extensions may be formedat an angle to allow the plug 700 to be more easily removed from theport 201. Similarly, the distal end 705 of one or more extensions 703may be formed at a slight angle downward to allow the present inventionto be more easily inserted into a port 201. It will be clear to those ofordinary skill in the art, that a number of alternative shapes may beused, as shown in FIGS. 8a-8 e. FIG. 8a shows the present inventionformed as a cross. Accordingly, each of the extensions 801 areessentially rectangular. As shown in FIG. 8b, the present invention hasextensions 803 which are notched at the distal end 805. As shown in FIG.8b, the width of each extension 803 is less than the diameter of acentral circular body 809 divided by the square root of 2. Accordingly,a portion 807 of the perimeter of the central circular body 809 forms apart of the perimeter of the plug 800. FIG. 8c illustrates an embodimentof the present invention in which four generally triangular shapedextensions 811 are provided. FIG. 8d illustrates an embodiment in whichfour relatively smaller generally triangular extensions 813 areprovided. FIG. 8e illustrates an embodiment of the present inventionwhich extensions 815 are generally rectangular having rounded distalends 817. It will be clear to those skilled in the art that numerousother shapes and configurations are possible. Those illustrated in FIGS.1 through 8 are merely provided as exemplars.

FIG. 9a illustrates yet another embodiment of the present invention. Theplug 900 in FIG. 9a may be vacuum-formed from a sheet of plastic. Theplug 900 preferably has a flange 901 which is larger in diameter thaninlet port 201 with which the plug 900 is to be used. The flangeprevents the plug 900 from passing completely though the port 201. Theinvention has a generally vertical ring-like surface 903 that press fitsinto the inlet port 201. Accordingly, the diameter of the surface 903 isessentially equal of the diameter of the port 201 with which the plug900 is to be used. The flange 901 preferably has a tab 905 which extendstherefrom. The tab 905 provides the user with a handle to grasp whenremoving the plug 900 from a port 201.

Protruding from the wall 903 are a plurality of protuberances 907 whichextend radially outward from the wall 903. Each protuberance 907 has anupper and lower slope 909, 911, respectively. The upper and lower slopes909, 911 allow the plug 900 to be inserted and removed relativelyeasily, while resisting removal of the plug 900 from the port 201, suchthat the plug 900 is retained under normal conditions but may be easilyremoved when desired.

In accordance with one embodiment of the present invention, the flange901 is sufficiently thick to allow the user to comfortably grasp theplug 900 when the plug 900 is fully inserted into an insertion port 201.For example, in one embodiment, the flange 901 is approximately 0.25inches thick

In one embodiment of the present invention shown in FIG. 9b theprotuberances 907 are retractable, and retract along the path indicatedby arrow 913. When force is applied against the protuberance 907, an arm915 flexes. A slit 917 frees the arm 915 from the wall 903 and allowsthe protuberance 907 to retract. FIG. 11 shows the plug 900 suspendedabove the port 201 prior to insertion into the port. FIG. 12 illustratesthe plug 900 after insertion into the port 201.

FIG. 13 illustrates yet another alternative embodiment to the presentinvention. The plug 1300 is preferably molded from plastic. The plug1300 is retained in the port 201 by spiral groves 13 molded/etched intothe edges of the plug 1300 to form threads 1303. The plug 1300 may bescrewed into the port 201, and later unscrewed from the port 201. Theplug 1300 preferably has a flange 1301 which is larger than the port201. The body 1305 of the plug 1300 preferably has a diameter which isequal to or slightly larger than the diameter of the port 201. FIG. 14is an illustration of the plug 1300 after insertion into a port 201.Only the flange 1301 is visible in FIG. 14.

FIG. 15 illustrates the present invention 100 in use with a conventionalupper body inflatable thermal blanket 1501. FIG. 16 shows the presentinvention 100 in use with a lower body inflatable thermal blanket 1601.The invention may generally be used with these and other inflatablethermal blankets.

SUMMARY

A number of embodiments of the present invention have been described.Nevertheless, it will be understood that various modifications may bemade without departing from the spirit and scope of the invention. Forexample, the plugs shown in FIGS. 1-6 may be fabricated from anygenerally resilient sheet of material.

Furthermore, the nature of the material which defines the inlet port isnot critical to the present invention. Accordingly, the sheet whichforms the inlet port may be cardboard, plastic metal, ceramic, or anyother material Still further, the protuberances 907 shown in FIGS. 9a-12may form a single continuous ring about the ring-like vertical wall 903.Still farther yet, the angle of the lower and upper slope 909, 911 ofthe embodiment of the present invention shown in FIGS. 9a-12, may differsubstantially from one another. Also, the plug 900 shown in FIGS. 9a-12may be formed without the tab 905, and the flange may be formed at anangle other than 90° with the vertical wall 903.

Accordingly, it is to be understood that the invention is not to belimited by the specific illustrated embodiment, but only by the scope ofthe appended claims.

What is claimed is:
 1. An apparatus for closing an inlet port,comprising: a sheet of material; an inlet port in the sheet of material,the inlet port having a shape for receiving an air hose nozzle; and aplug with a generally planar body and a plurality of extensionssubstantially coplanar with the body which extend radially from thebody, at least two extensions of the plurality of extensions for beingreceived into the inlet port in order to retain the plug over the inletport.
 2. The apparatus of claim 1, wherein at least one of theextensions is circular.
 3. The apparatus of claim 1, wherein at leastone of the extensions is triangular.
 4. The apparatus of claim 1,wherein at least one of the extensions is rectangular.
 5. The apparatusof claim 1, wherein the extensions are formed from a resilient material.6. The apparatus of claim 1, wherein at least one of the extensions hasa distal end which is not coplanar with the body.
 7. The apparatus ofclaim 1, wherein at least one of the extensions has a distal end whichis formed at an angle to the extension.
 8. The apparatus of claim 1,wherein at least one of the extensions has a distal end which isnotched.
 9. The apparatus of claim 1, wherein the plug comprises aplastic material.
 10. The apparatus of claim 1, wherein the plugcomprises a wood pulp material.
 11. The apparatus of claim 1, whereinthe plurality of extensions includes an even number of opposingextensions.
 12. The apparatus of claim 11, wherein the plurality ofextensions includes two or more pairs of opposing extensions.
 13. Theapparatus of claim 11, wherein the plug includes three pairs of opposingextensions.